As we will discover, Ethel Wilson actually uses assumed chronology in Innocent Traveller as a device by which to represent in fiction the real effects that past and future have on present. The "Innumerable Laughter" chapter, for example, has Topaz Edgeworth's present experience of a sleep-out in the veranda materially transformed by one particular girlhood experience with her private teacher, Mrs. Porter. Or the following from "'By our First Strange and Fatal Interview'": "Mary was hardly prepared to see the future leap out into the open and transform her past into something which was not enough. But this was now achieved by the young man in black walking by her side."
The idea used by Ethel Wilson -- of Time as an efficient cause -- is not simply a fictional conceit. In contemporary Western society, Time is assumed thoughtlessly to be what a clock does: a rigid linear series of equal units. This was not the experience or understanding of time, certainly, in the pre-modern West, and likely not either in non-Western cultures.
Ethel Wilson is arguably first post-modern writer. Innocent Traveller certainly, as I read it, is in sympathy with Albert Einstein's relativity theory (again, insofaras this layman understands it.)
e = mc2 (energy equals mass multiplied by the square of the speed of light) is an equation that represents matter as being energy at a particular speed. For students of fiction this has as one important implication that the thoughts and actions of characters -- i.e. forms of energy -- have real and significant effects on the material world and on the movement of history, making the writing, reading and academic study of fictional representations of life a worthy enterprise.
Of interest to our understanding of Wilson's fiction is the fact that Einstein's equation also defines Time as being Matter and Energy in a certain relation. Reformulate e = mc2 as c = [root] e/m.
Reading this formula in a fictional way, then: if we read Wilson's novel as representing the human spirit as energy (Topaz a personification of energy) and the circumstances of the world (marriages, emigrations, etc.) as matter (using "matter" in the colloquial British sense) then the depictions of Time that Wilson has woven throughout her narrative are to be read by us as having the same reality as matter and energy do in our ordinary understanding
But to continue with the exercise, to help understand how the "c" - speed of light - in Einstein's relativity equation relates to Time, just look at it this way.
Think of distance ("D") as being a change in place ("ΔP"). And Speed in general is represented as velocity ("V"). And of course Time is "T". You'll remember from High-School that the formula for velocity is V = ΔP / T. (Recall that we're saying that "D" is the same as "ΔP"). If we recast this equation for Time "T", then T = ΔP / V
So, if our velocity "V" is a particular value - using Einstein's speed of light "c" - then c = ΔP / T and T = ΔP /c.
Now returning to fiction. This last formulation lets us read Innocent Traveller (the traveller is the one ΔP'ing!) as showing us that Topaz's travels - to Vancouver, then to ... where? - and her velocity (Wilson depicts Topaz as perpetual rapidity of speech) are a form of Time. Or in other words, Topaz did have an effect on Time-with-a-capital-T: or, in the word the text uses at important points, on Eternity.
This, then, is what Rose/Ethel sets out to achieve through her narrative fiction - an eternal life for her Aunt Topaz/Eliza.
Physics, Mathematics, &c. experts more than encouraged to correct the forumlæ.